TY - JOUR
T1 - Environmental impacts of shifts in energy, emissions, and urban heat island during the COVID-19 lockdown across Pakistan
AU - Ali, Ghaffar
AU - Abbas, Sawaid
AU - Qamer, Faisal Mueen
AU - Wong, Man Sing
AU - Rasul, Ghulam
AU - Irteza, Syed Muhammad
AU - Shahzad, Naeem
N1 - Funding Information:
This research was supported in part by the Climate Service Initiative of the International Center for Integrated Mountain Development (ICIMOD); by a grant ( 1-BBWD ) from the Research Institute for Sustainable Urban Development , the Hong Kong Polytechnic University, Hong Kong SAR ; and by another two grants ( 15602619 and PolyU 152164/18 E ) from the Research Grants Council (RGC) of Hong Kong SAR, China. The authors are grateful to NASA, Copernicus Sentinel, ESA, and LP DAAC for providing their data sets. We also acknowledge the Google Earth Engine cloud computing platform and its vibrant and helping community. The views and interpretations in this paper are those of the authors and are not necessarily attributable to their institutions. The boundaries, names, and designations indicated on the maps do not imply the expression of authors or their institutions opinion concerning the legal status of any country, territory, city, area, their associated authorities, or demarcations of their frontiers orboundaries.
Publisher Copyright:
© 2021 The Author(s)
PY - 2021/4/1
Y1 - 2021/4/1
N2 - Restrictions on human and industrial activities due to the coronavirus (COVID-19) pandemic have resulted in an unprecedented reduction in energy consumption and air pollution around the world. Quantifying these changes in environmental conditions due to government-enforced containment measures provides a unique opportunity to understand the patterns, origins and impacts of air pollutants. During the lockdown in Pakistan, a significant reduction in energy demands and a decline of ∼1786 GWh (gigawatt hours) in electricity generation is reported. We used satellite observational data for nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2), aerosol optical depth (AOD) and land surface temperature (LST) to explore the associated environmental impacts of shifts in energy demands and emissions across Pakistan. During the strict lockdown period (March 23 to April 15, 2020), we observed a reduction in NO2 emissions by 40% from coal-based power plants followed by 30% in major urban areas compared to the same period in 2019. Also, around 25% decrease in AOD (at 550 nm) thickness in industrial and energy sectors was observed although no major decrease was evident in urban areas. Most of the industrial regions resumed emissions during the 3rd quarter of April 2020 while the urban regions maintained reduced emissions for a longer period. Nonetheless, a gradual increase has been observed since April 16 due to relaxations in lockdown implementations. Restrictions on transportation in the cities resulted in an evident drop in the surface urban heat island (SUHI) effect, particularly in megacities. The changes reported as well as the analytical framework provides a baseline benchmark to assess the sectoral pollution contributions to air quality, especially in the scarcity of ground-based monitoring systems across the country.
AB - Restrictions on human and industrial activities due to the coronavirus (COVID-19) pandemic have resulted in an unprecedented reduction in energy consumption and air pollution around the world. Quantifying these changes in environmental conditions due to government-enforced containment measures provides a unique opportunity to understand the patterns, origins and impacts of air pollutants. During the lockdown in Pakistan, a significant reduction in energy demands and a decline of ∼1786 GWh (gigawatt hours) in electricity generation is reported. We used satellite observational data for nitrogen dioxide (NO2), carbon monoxide (CO), sulphur dioxide (SO2), aerosol optical depth (AOD) and land surface temperature (LST) to explore the associated environmental impacts of shifts in energy demands and emissions across Pakistan. During the strict lockdown period (March 23 to April 15, 2020), we observed a reduction in NO2 emissions by 40% from coal-based power plants followed by 30% in major urban areas compared to the same period in 2019. Also, around 25% decrease in AOD (at 550 nm) thickness in industrial and energy sectors was observed although no major decrease was evident in urban areas. Most of the industrial regions resumed emissions during the 3rd quarter of April 2020 while the urban regions maintained reduced emissions for a longer period. Nonetheless, a gradual increase has been observed since April 16 due to relaxations in lockdown implementations. Restrictions on transportation in the cities resulted in an evident drop in the surface urban heat island (SUHI) effect, particularly in megacities. The changes reported as well as the analytical framework provides a baseline benchmark to assess the sectoral pollution contributions to air quality, especially in the scarcity of ground-based monitoring systems across the country.
KW - Air pollution
KW - COVID-19
KW - Energy emissions
KW - Lockdown
KW - Nitrogen dioxide (NO)
KW - Pakistan
UR - http://www.scopus.com/inward/record.url?scp=85099522235&partnerID=8YFLogxK
U2 - 10.1016/j.jclepro.2021.125806
DO - 10.1016/j.jclepro.2021.125806
M3 - Journal article
AN - SCOPUS:85099522235
SN - 0959-6526
VL - 291
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
M1 - 125806
ER -